I am currently reviewing the Water-to-Go filter bottle and have found it a robust and well designed bit of kit. It is made of tough plastic with a rubber sleeve to improve your grip. It has a wide neck which aids water collection and it also has a lever on the nozzle that makes it easy to flip out without contaminating the mouth part.
Over the last few months I have used it in a variety of situations; for example, on survival courses, while hill walking, canoeing and in places where I would be wary of drinking the water without treatment. In fact the water supply to my house comes directly from a hill stream and drinking it through the Water-to-Go bottle reduces the irony taste, improves the clarity and seems to increase hydrating quality of the water.
I am sufficiently impressed with Water-to-Go that I am considering selling them on my survival courses.